Begin working on checklist

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 205 insertions, 0 deletions

diff --git a/checklist.c b/checklist.c
new file mode 100644
index 0000000..5d7e261
--- /dev/null
+++ b/checklist.c
@@ -0,0 +1,205 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+
+/* TODO Add support for comments (indent the next line in the file with a tab) */
+
+USAGE("");
+
+
+struct entry {
+	struct entry *next;
+	struct entry *prev;
+	struct entry *in;
+	struct entry *out;
+	struct entry *flat_next;
+	char status;
+	char text[];
+};
+
+
+static struct entry *
+load(const char *path)
+{
+	struct entry *entry, *ret = NULL, *tail = NULL, *parent = NULL;
+	FILE *fp;
+	char *line = NULL;
+	size_t size = 0, lineno = 0, indent = 0, i;
+	ssize_t len;
+
+	fp = fopen(path, "r");
+	if (!fp) {
+		if (errno == ENOENT)
+			return NULL;
+		eprintf("fopen %s \"r\":", path);
+	}
+
+	while ((len = getdelim(&line, &size, '\n', fp)) >= 0) {
+		lineno += 1;
+		if (len && line[len - 1] == '\n')
+			line[--len] = '\0';
+		for (i = 0; line[i] == ' '; i++);
+		if (i == (size_t)len)
+			eprintf("line %zu in %s is malformatted 1\n", lineno, path);
+		if (i > indent + (size_t)!!ret)
+			eprintf("line %zu in %s is malformatted 2 %zu > %zu + %i\n", lineno, path, i, indent, !!ret);
+		entry = ecalloc(1, offsetof(struct entry, text) + (size_t)len - i);
+		if (!ret)
+			ret = entry;
+		else
+			tail->flat_next = entry;
+		entry->status = line[i];
+		if (entry->status != '_' && /* unmarked, displayed as [ ] */
+		    entry->status != 'X' && /* done */
+		    entry->status != '-' && /* not now */
+		    entry->status != '/' && /* partially done */
+		    entry->status != '!' && /* important */
+		    entry->status != '?')   /* maybe */
+			eprintf("line %zu in %s is malformatted\n", lineno, path);
+		stpcpy(entry->text, &line[i + 1]);
+		if (i == indent) {
+			entry->prev = tail;
+			if (tail)
+				tail->next = entry;
+			entry->out = parent;
+		} else if (i > indent) {
+			indent += 1;
+			entry->out = tail;
+			tail->in = entry;
+			parent = entry->out;
+		} else {
+			while (--indent > i)
+				parent = parent->out;
+			entry->prev = parent;
+			parent->next = entry;
+			parent = parent->out;
+			entry->out = parent;
+		}
+		tail = entry;
+	}
+
+	if (ferror(fp))
+		eprintf("getdelim %s:", path);
+
+	fclose(fp);
+	free(line);
+	return ret;
+}
+
+
+static struct entry *
+get_next(struct entry *entry, size_t *indentp)
+{
+	if (entry->in) {
+		++*indentp;
+		return entry->in;
+	}
+	if (entry->next)
+		return entry->next;
+	while (entry->out) {
+		entry = entry->out;
+		--*indentp;
+		if (entry->next)
+			return entry->next;
+	}
+	return NULL;
+}
+
+
+static int
+save(const char *path, const char *tmppath, struct entry *head)
+{
+#define SPACES "                "
+
+	int fd, saved_errno;
+	size_t indent = 0, n, off;
+	ssize_t r;
+
+	fd = open(tmppath, O_WRONLY | O_CREAT | O_TRUNC, 0666);
+	if (fd < 0)
+		return -1;
+
+	for (; head; head = get_next(head, &indent)) {
+		for (n = indent; n; n -= (size_t)r) {
+			r = write(fd, SPACES, indent < sizeof(SPACES) - 1 ? indent : sizeof(SPACES) - 1);
+			if (r < 0)
+				goto fail;
+		}
+		if (write(fd, &head->status, 1) < 1)
+			goto fail;
+		n = strlen(head->text);
+		for (off = 0; off < n; off += (size_t)r) {
+			r = write(fd, &head->text[off], n - off);
+			if (r < 0)
+				goto fail;
+		}
+		if (write(fd, &(char){'\n'}, 1) < 1)
+			goto fail;
+	}
+
+	if (fsync(fd)) {
+	fail:
+		saved_errno = errno;
+		close(fd);
+		errno = saved_errno;
+		return -1;
+	}
+	if (close(fd) || rename(tmppath, path))
+		return -1;
+
+	return 0;
+
+#undef SPACES
+}
+
+
+static char *
+get_path(void)
+{
+	struct passwd *user;
+	size_t homelen;
+	char *ret;
+
+	errno = 0;
+	user = getpwuid(getuid());
+	if (!user)
+		eprintf("getpwuid: %s\n", errno ? strerror(errno) : "user does not exist");
+	if (!user->pw_dir || !*user->pw_dir)
+		eprintf("user does not have a home directory\n");
+	if (access(user->pw_dir, R_OK | W_OK | X_OK))
+		eprintf("access %s R_OK|W_OK|X_OK:", user->pw_dir);
+
+	homelen = strlen(user->pw_dir);
+	if (homelen && user->pw_dir[homelen - 1] == '/')
+		homelen -= 1;
+
+	ret = emalloc(homelen + sizeof("/.var/lib/pdatools/checklist"));
+	memcpy(ret, user->pw_dir, homelen);
+	memcpy(&ret[homelen], "/.var/lib/pdatools/checklist", sizeof("/.var/lib/pdatools/checklist"));
+	return ret;
+}
+
+
+int
+main(int argc, char *argv[])
+{
+	char *path, *tmppath;
+	struct entry *head, *node;
+	size_t indent;
+
+	NOFLAGS(argc);
+
+	path = get_path();
+	tmppath = emalloc(strlen(path) + 2);
+	stpcpy(stpcpy(tmppath, path), "~");
+	head = load(path);
+
+	/* TODO */
+	indent = 0;
+	for (node = head; node; node = get_next(node, &indent))
+		printf("%*.s[%c] %s\n", (int)indent * 2, "", node->status, node->text);
+
+	for (node = NULL; free(node), head; node = head, head = head->flat_next);
+	free(path);
+	free(tmppath);
+	return 0;
+}